ESTIMATION OF IONIZATION-CONSTANTS OF AZO DYES AND RELATED AROMATIC-AMINES - ENVIRONMENTAL IMPLICATION

Ionization constants for 214 dye molecules were calculated from molecu lar structures using the chemical reactivity models developed in SPARC (SPARC Performs Automated Reasoning in Chemistry). These models used fundamental chemical structure theory to predict chemical reactivities for a wide range of organic molecules from molecular structure. The e nergy differences between the protonated state and the unprotonated st ate for a molecule of interest are factored into mechanistic component s including the electrostatic and resonance contributions and any addi tional contributions to these energy differences. The RMS deviation wa s found to be less than 0.62 pK. units, which is similar to the experi mental error.